.TH SETWFDB 1 "12 June 2005" "WFDB 10.3.16" "WFDB Applications Guide"
.SH NAME
setwfdb, cshsetwfdb \- set WFDB environment variables
.SH SYNOPSIS
\fB\&. setwfdb\fR
.br
\fBsource cshsetwfdb\fR
.br
\fBcall setwfdb\fR
.SH DESCRIPTION
.PP
WFDB applications search for input files by looking for them in an
ordered list of locations called the \fIWFDB path\fR.  These locations can
be given by directory names or (if the WFDB library has been installed
with \fBNETFILES\fR support) URLs.  If the \fBWFDB\fR environment variable
is set, its value specifies the WFDB path; otherwise, applications use
the builtin default path specified at the time the WFDB library was compiled.
The default path (\fBDEFWFDB\fR, defined in the WFDB library source file
\fBwfdblib.h\fR) includes the current directory (``.''), the system-wide
database directory installed as part of the WFDB Software Package (usually
\fB/usr/database\fR), and
the PhysioBank data archive (http://www.physionet.org/physiobank/database).
.PP
WFDB applications that need access to the signal calibration database
find it in a file located on the WFDB path.  If the \fBWFDBCAL\fR
environment variable has been set, its value specifies the name of the
calibration file;  otherwise, applications look for the default calibration
file, the name of which (\fBwfdbcal\fR) is compiled into the WFDB library.
.PP
Many users will not need to change the defaults, but for those who do, the
scripts described here may be helpful.  \fIImportant:\fR these programs must
be customized before using them for the first time on a new machine.  Since
they are text files, use any text editor to customize them.
.SS \fBsh\fR, \fBbash\fR, and \fBksh\fR users:
\fBsetwfdb\fR sets the environment variables \fBWFDB\fR and
\fBWFDBCAL\fR.  It must be executed using the ``.'' as shown above.
It may be convenient to include an invocation of \fBsetwfdb\fR in
your \fB.profile\fR file.
.SS \fBcsh\fR and \fBtcsh\fR users:
\fBcshsetwfdb\fR sets \fBWFDB\fR and \fBWFDBCAL\fR similarly for the C-shell.
It must be executed using ``source'' as shown above.  It may be convenient to
include this command in your \fB.cshrc\fR file.
.PP
.SH ENVIRONMENT
.TP
\fBWFDB\fR
The database path: a list of directories that contain database files.
An empty component is taken to refer to the current directory.  All
applications built with the \fBwfdb\fR(3) library search for their
database input files in the order specified by \fBWFDB\fR.  If
\fBWFDB\fR is not set, searches are limited to the builtin WFDB path
(see above).  Under Unix, directory names are separated by colons (:),
and the format of \fBWFDB\fR is that of the Bourne shell's \fBPATH\fR
variable (see \fBsh\fR(1)).  Under MS-DOS, directory names are separated
by semicolons (;), and the format of \fBWFDB\fR is that of the MS-DOS
\fBPATH\fR variable (colons may be used following drive specifiers
within \fBWFDB\fR in this case).  MacOS does not support
environment variables as such; under MacOS, the builtin WFDB path
is defined in \fBfdblib.h\fR as described above, and it
contains a semicolon-delimited list of directories (folders) as under
MS-DOS, but with colons used as directory separators rather than
backslashes as under MS-DOS.  Alternatively, whitespace can be used
(under any environment) to separate components of the WFDB path.
Under any environment, if the value of \fBWFDB\fR begins with `@', the
remainder of the string is taken as the name of an ``indirect WFDB path
file'' that defines the database path in the format described above.
 This feature was introduced in WFDB library version 8.0, mainly to permit
MacOS users to modify the WFDB path without recompiling the WFDB library,
but it is also useful under MS-DOS to avoid the 128-character limit on the
length of environment variables.  Indirect WFDB path files can be nested
up to 10 levels deep.
.TP
\fBWFDBCAL\fR
The name of the WFDB calibration file (see \fBwfdbcal\fR(5)).  The
usual rules for finding WFDB files by searching the WFDB path apply to
the WFDB calibration file, so the value of \fBWFDBCAL\fR need not be
an absolute path name.  The WFDB calibration file is used by WFDB
applications that need to plot signals at standard scales, as well as
by \fBcalsig\fR(1), which can determine the baseline and gain of
signals if calibration pulses are present and if the parameters of the
calibration pulses are described in the calibration file.  If
\fBWFDBCAL\fR is not set by the user, the WFDB library uses a default
WFDB calibration file (\fBwfdbcal\fR, named in \fBwfdblib.h\fR).  If
the WFDB calibration file is not readable, programs that rely on it
may not choose appropriate scales for some types of signals.
.SH AUTHOR
George B. Moody (george@mit.edu)
.SH SOURCES
Note that these are \fItemplates\fR and will need to be customized
before use:
.br
http://www.physionet.org/physiotools/wfdb/app/setwfdb
.br
http://www.physionet.org/physiotools/wfdb/app/cshsetwfdb
